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Simulation optimization is an approach that is used to solve problems involving stochastic components. This paper presents a Lexicographic Nelder-Mead (LNM) based simulation optimization (LNM-SO) method to solve multi-criteria simulation optimization problems. The method is designed to be relatively easy-to-implement and be applicable to a wide range of problem domains. To effectively evaluate the overall performance of this method, a Time-Quality Estimator (TQE) was developed to evaluate the performance of LNM-SO in terms of both quality of solution and computational speed. Computational results of five different test problems showed that the method was highly effective.

This research proposes a Web-based version of a lean office simulation game (WeBLOG). The game is designed to be used to train lean concepts to office and administrative personnel. This group belongs to the frequently forgotten side of a lean enterprise. Over four phases, the game presents the following seven lean tools: one-piece flow, error-proofing, elimination of overprocessing, balanced workload, multifunctional workforce, pull, and total quality. The concept of continuous improvement is also covered. Participants can play the game from remote and separate locations by logging into a specified Internet site. Additionally, the game can be played with a combination of real and virtual (simulated) players. Several performance metrics are automatically calculated and displayed at the conclusion of each phase. The results of the current phase can then be compared to the results from all previous phases to better illustrate the impact of newly introduced lean tools.

The study described in this paper investigated the possible interference of spurious emissions from cellular phones on aircraft navigation and communication equipment. Six wireless phone technologies were investigated over three frequency ranges, which covered the receiving ranges of five aircraft systems. The aircraft systems examined were very-high frequency omnidirectional range (VOR), localizer (LOC), very high frequency communication (VHF), glide slope (GS), and global positioning system (GPS). Research was performed in a semi-anechoic chamber (SAC) and a reverberation chamber (RC), with the phone at a distance of 1 m from the receiving antenna. Two antenna orientations were tested in the SAC. Initial tests yielded the appropriate height from the receiving antenna above the ground plane that would produce a maximum field measurement. Keypad programming was used to simulate worst-case phone transmissions. Radiated power measurements were performed and analyzed taking into consideration path loss results from the RTCA/DO-233 study. None of the six phone technologies investigated exhibited a power level greater than a 38-dBm path loss level above the maximum sensitivity of the aircraft system antennae when tested 1 m away from the antenna. These results indicate that, for the aircraft systems tested (VOR, LOC, VHF, GS, and GPS), the antenna of these systems would not have detected the emissions of the phones used in this study (CDMA-cellular, TDMA-11 Hz, TDMA-50 Hz cellular and PCS, GSM, and DCS-1800).

Los principios de Lean Manufacturing se usan principalmente para mejorar la productividad, reducir el tiempo de entrega y eliminar desperdicios. Los impactos en consumo de energía también se pueden estimar usando principios de Lean. El objetivo de este artículo es el de medir el impacto del uso de herramientas de Lean Manufacturing en el consumo de energía, partiendo del supuesto de que su aplicación debería reducirlo. La metodología evalúa y documenta la utilización de la energía como parte de la elaboración de Mapas de la Cadena de Valor. Finalmente se presenta una aplicación piloto en una empresa industrial. Lean principles are mainly used for increasing productivity, reducing lead time, and eliminating waste. Energy impacts can also be assessed by using the lean principles. The objective of this paper is to measure the impact of Lean Manufacturing tools on energy consumption, with the base assumption that they should help decrease it. The methodology assesses and documents the energy utilization as a part of VSM. A pilot application in an industrial setting is presented.